The naked truths of the holocaust

KZ is the German for concentration camp (a derivation of Konzentrationslager) and Mauthausen, on the beautiful banks of the Danube, was one of the worst of the Nazi killing houses.

Now "Holocaust tourism" is the order of the day there and busloads of the curious, including schoolchildren, walk through the camp and are told by guides of the horrors therein.

British director Rex Bloomstein's impressively calm documentary shows no sequences that make us want to look away.

But he does interview the locals, most of whom claim not to have known what was going on, and a veteran guide who says that telling and retelling his terrible stories has made him an alcoholic.

One young schoolgirl faints when she's told of what happened at the camp.

But all is not shame, guilt and horror. The veteran guide, taking a party into the gas chambers, points to the ceiling. "There were showerheads there to stop people panicking," he says, "But they've gone now. People have taken them for souvenirs."